JP6550962B2 - Epitaxial growth equipment for silicon carbide semiconductor - Google Patents

Description

  The present invention relates to an epitaxial growth apparatus capable of epitaxially growing a silicon carbide (hereinafter referred to as SiC) semiconductor.

  Conventionally, Patent Document 1 proposes a chemical vapor deposition (CVD) apparatus capable of reducing the frequency of maintenance while uniformly supplying a gas to the surface of a SiC semiconductor substrate. In this CVD apparatus, a plate-like inlet equipped with a cooling mechanism is used so that maintenance frequency can be reduced by minimizing deposits on the inlet.

  Specifically, as shown in FIG. 9, a plurality of holes are provided in a flat inlet J1 to form a gas introduction hole J2, and Si (silicon) is formed from each gas introduction hole J2 into a reaction chamber in which epitaxial growth is performed. Si source gas containing C and C source gas containing C (carbon) are supplied. In addition, the dopant gas of the p-type impurity is supplied from a gas introduction hole J2 different from that to which the Si source gas or the C source gas is introduced. A cooling water passage J4 through which the cooling water J3 is caused to flow is provided in the inlet J1 in which the gas introduction hole J2 is formed, and the inlet J1 is cooled.

Special table 2008-508744

  However, as shown in FIG. 9, since the tip on the reaction chamber side of the inlet J1 is flat, stagnation of the gas flow as shown by the broken arrow in the figure may occur. As a result, there is a problem that the dopant gas convects and the controllability of the carrier concentration in the depth direction of the SiC semiconductor layer to be epitaxially grown is deteriorated. That is, it is difficult to realize a structure in which the carrier concentration is sharply changed in the depth direction of the SiC semiconductor layer to be epitaxially grown. In particular, in the case where epitaxial growth is performed in a high temperature atmosphere such as a SiC semiconductor, the temperature gradient in the vicinity of the inlet is large, and the stagnation of the gas flow tends to occur.

  An object of the present invention is to provide an epitaxial growth apparatus for a SiC semiconductor capable of forming carrier concentration of an epitaxially grown SiC semiconductor layer with good controllability.

  In order to achieve the above object, according to the invention as set forth in claim 1, the chamber (20) constituting the growth chamber, the growth chamber provided in the chamber, and the installation in which the SiC semiconductor substrate (70) is installed A susceptor portion (50) constituting a surface, a plurality of separation chambers (40) into which a dopant gas including an Si source-containing gas, a C source-containing gas, and an element serving as an impurity of a SiC semiconductor is introduced An inlet (30) having gas inlets (31a to 31d) for introducing a gas introduced into the chamber into the growth chamber, and a heater (60) for heating the SiC semiconductor substrate. The Si source material containing gas, the C source material containing gas, and the dopant gas are introduced into the growth chamber through the gas inlet while heating the SiC semiconductor substrate on the SiC semiconductor substrate. An epitaxial growth apparatus for epitaxially growing a body layer, wherein an inlet partitions a plurality of separation chambers and a growth chamber, constitutes a gas inlet, and has an inlet opening portion (34) provided with a cooling mechanism (35) inside. And the inlet component has a plurality of concentrically arranged frame-like components (34a to 34c), and a gas inlet is interposed between the components. The plurality of constituent parts are tapered because the wall surface constituting the gas inlet among the plurality of constituent parts is inclined with respect to the direction from each of the plurality of separation chambers toward the growth chamber. It is characterized in that the wall surface is inclined to the tip on the growth chamber side most among the plurality of components.

  As described above, the wall surface is inclined to the tip on the growth chamber side of the plurality of components. That is, it is set as the structure without a flat surface at the front-end | tip of a some structure part. For this reason, it is possible to suppress the occurrence of gas flow stagnation at the tip of the component. For this reason, it can suppress that a dopant gas convects, and it becomes possible to adjust the carrier concentration contained in a SiC semiconductor layer with sufficient controllability.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows an example of a corresponding relationship with the specific means as described in embodiment mentioned later.

1 is a cross-sectional view of an epitaxial growth apparatus 10 according to a first embodiment of the present invention. It is II-II sectional drawing of FIG. It is sectional drawing which showed the gas flow from the inlet 30 in FIG. It is the figure which showed the relationship between carrier concentration and depth. It is sectional drawing of the epitaxial growth apparatus 10 concerning 2nd Embodiment of this invention. It is sectional drawing of the epitaxial growth apparatus 10 concerning 3rd Embodiment of this invention. It is sectional drawing of the epitaxial growth apparatus 10 concerning 4th Embodiment of this invention. It is sectional drawing which showed the front-end | tip shape of inlet part structure part 34a-34c demonstrated by other embodiment. It is sectional drawing which showed the gas flow from the conventional inlet J1.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same as or equivalent to each other will be described with the same reference numerals.

First Embodiment
An SiC semiconductor epitaxial growth apparatus 10 according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. 2 corresponds to the II-II sectional view of FIG. 1, and FIG. 1 corresponds to the II sectional view of FIG.

  As shown in FIG. 1, the epitaxial growth apparatus 10 for a SiC semiconductor is configured to include a chamber 20, an inlet 30, a separation chamber 40, a susceptor unit 50, and a heater 60. The epitaxial growth apparatus 10 is installed so that the vertical direction of the drawing in FIG.

  The chamber 20 is made of, for example, a metal such as SUS, and is made of a cylindrical member having a hollow portion that forms a growth chamber. The epitaxial growth apparatus 10 includes a separation chamber 40 constituted by an inlet 30 at an upper position inside the chamber 20, and a susceptor portion 50 at a lower position of the separation chamber 40, and an SiC installed in the susceptor portion 50. SiC semiconductor layer 80 is epitaxially grown on the surface of semiconductor substrate 70.

  The chamber 20 is provided with a cooling mechanism 21. The cooling mechanism 21 constitutes a flowing water path through which, for example, the cooling water 22 is circulated. A cooling water inlet and a flowing water outlet (not shown) are formed, and the cooling water 22 is introduced from the flowing water inlet and discharged from the flowing water outlet. Thus, the chamber 20 can always be cooled. For example, the side wall 23 of the chamber 20 is provided with a partition wall extending in the vertical direction to partition the chilled water path, and a running water inlet and a running water outlet are provided on both sides of the partition wall, thereby 22 are made to flow along the circumferential direction of the side wall 23 of the chamber 20. Further, in the figure, the bottom surface 24 of the chamber 20 is shown as a structure in which a flowing water path is provided in substantially the entire region, but for example, a flowing water path is provided in a spiral shape, and a flowing water inlet and a flowing water outlet are provided at both ends of the spiral. Thus, the cooling water 22 is allowed to flow spirally.

  A gas discharge port 25 is provided on the bottom surface 24 of the chamber 20, and the gas discharge from the inside of the chamber 20 is performed through the gas discharge port 25.

  The inlet 30 introduces gas while constituting the upper lid of the chamber 20, and is made of a metal such as SUS, for example. The inlet 30 forms first to fourth chambers 40a to 40d as the separation chamber 40 inside and communicates each of the first to fourth chambers 40a to 40d with the internal space provided in the chamber 20 to introduce the gas. The gas inlets 31a to 31d are provided. Specifically, the inlet 30 has a plate-like portion 32, a partition wall 33 disposed on the lower surface of the plate-like portion 32 (inside the chamber 20), and an inlet configuration provided at the tip of the partition wall 33. And a portion 34.

  The plate-like portion 32 constitutes the upper lid of the chamber 20, and in the case of this embodiment, is constituted by a disk-like member. Gas inflow holes 32a to 32d are formed at positions corresponding to the first to fourth chambers 40a to 40d in the plate-like portion 32, and gas to the first to fourth chambers 40a to 40d is formed through the gas inflow holes 32a to 32d. Inflow takes place.

  The partition wall part 33 plays a role of partitioning the first to fourth rooms 40a to 40b as a space. Specifically, the partition wall portion 33 is constituted by a circular frame-shaped projection portion concentrically arranged from the center of the plate-like portion 32. The partition wall 33 includes a first partition wall 33a that surrounds the periphery of the first room 40a, a second partition wall 33b that surrounds the first partition wall 33a and forms the second chamber 40b between the first partition wall 33a, A third partition wall 33c that surrounds the second partition wall 33b and forms the third chamber 40c between the second partition wall 33b, and a fourth chamber 40d that surrounds the third partition wall 33c and between the third partition wall 33c The fourth partition wall 33d is provided. Since each of the first to fourth partition walls 33a to 33d has a circular frame shape, the first room 40a is a circular shape, and the second to fourth rooms 40b to 40d are each an annular room.

  The inlet configuration unit 34 divides the first to fourth chambers 40a to 40d and the growth chamber in the chamber 20 and introduces various gases introduced into the first to fourth chambers 40a to 40d into the growth chamber. Gas inlets 31a to 31d are provided. As shown in FIG. 2, in this embodiment, the gas inlets 31a to 31d are a first inlet 31a that is circular, and an annular first that is concentrically provided around the first inlet 31a. It is comprised by 2nd-4th inlet 31b-31d. The first to fourth introduction ports 31a to 31d have the same opening width, specifically the radial dimension. However, the opening width is arbitrary, and may be different. For example, the opening width may increase in order from the first inlet 31a located at the center to the fourth inlet 31d located at the outermost side It may be reduced.

  The inlet structure part 34 is equipped with the cooling mechanism 35 in the inside, for example, it is made for cooling the inlet structure part 34 to 200 degrees C or less. The cooling mechanism 35 cools various gas introduced through the wall surfaces constituting the first to fourth inlets 31 a to 31 d and the first to fourth inlets 31 a to 31 d of the inlet configuration part 34. The adhesion of the deposit to the inlet structure 34 is suppressed. The deposits referred to here correspond to SiC, Al used as a dopant, and the like. Specifically, the inlet configuration section 34 is divided into first to third configuration sections 34a to 34c by the first to fourth inlets 31a to 31d, and the first to third configuration sections 34a to 34c, respectively. Is provided with a cooling mechanism 35.

  The cooling mechanism 35 constitutes, for example, a flowing water path through which the cooling water 36 is circulated, and a flowing water inlet and a flowing water outlet (not shown) are formed. And the cooling water 36 is introduce | transduced from the flowing water inlet with which the cooling mechanism 35 was equipped, and is discharged | emitted from a flowing water outlet, so that it can always cool the 1st-3rd components 34a-34c during epitaxial growth. . For example, a portion of the path through which the cooling water 36 is introduced is provided in the plate-like portion 32 and the partition wall portion 33, and the cooling water 36 is made to flow in the first to third component portions 34a to 34c. Yes. In that case, for example, it is possible to use an annular water flow path with a part cut away in the first to third components 34a to 34c, and use one end of the cut as a water flow inlet and the other end as a water flow outlet.

  In the growth chamber side of the chamber 20, the tips of the first to third component portions 34a to 34c are tapered. More specifically, among the first to third components 34a to 34c, the first to fourth introduction ports 31a with respect to the direction from the respective chambers 40a to 40d toward the growth chamber (normal direction with respect to the surface of the susceptor unit 50). The wall surfaces (side surfaces) constituting ~ 31d are inclined, and the opening widths of the first to fourth inlets 31a to 31d are gradually expanded toward the growth chamber side. In the case of the present embodiment, in the cross section shown in FIG. 1, a portion on the growth chamber side of the wall surface is linearly inclined to form a tapered surface. The wall surface is inclined to the most distal end on the susceptor unit 50 side among the first to third component portions 34a to 34c, and has a structure without a flat surface at the distal end.

  The gas inflow holes 32 a to 32 d serve as inlets for separately introducing a gas containing a raw material of the SiC semiconductor, a carrier gas, and the like into each of the first to fourth chambers 40 a to 40 d. In the case of the present embodiment, four types of first to fourth inflow holes 32a to 32d are provided as the gas inflow holes 32a to 32d, and various gases are respectively supplied from the first to fourth inflow holes 32a to 32d. Introduce. Specifically, the first to fourth inflow holes 32a to 32d are formed at positions corresponding to the first to fourth chambers 40a to 40d, respectively. Each of the first to fourth inflow holes 32a to 32d may be single or plural. In the case of the present embodiment, a plurality of second to fourth inflow holes 32 a to 32 d are concentrically arranged in the second to fourth chambers 40 b to 40 d which are, for example, annular.

  Gas pipes 41 to 44 are respectively connected to the first to fourth inflow holes 32 a to 32 d, and various gases are introduced through the gas pipes 41 to 44. Gas cylinders 45 to 48 are connected to the gas pipes 41 to 44, and flow control can be performed by mass flow controllers (hereinafter referred to as MFC) 41a to 41d, 42a to 42d, 43a to 43d, and 44a to 44d. Yes.

The gas cylinder 45 contains an Si source gas, and supplies a silane-based gas (for example, TCS (trichlorosilane)). The gas cylinder 46 contains C source gas and supplies propane-based gas (for example, C ₃ H ₈ (propane)). The gas cylinder 47 supplies a dopant gas (for example, TMA (trimethylaluminum)) containing a p-type impurity. The gas cylinder 48 contains a carrier gas and the like, and supplies, for example, H ₂ (hydrogen), an inert gas, and the like.

  Although an example of the Si source gas, the C source gas, the dopant gas, and the carrier gas is shown here, of course, other gases may be used.

  The separation chamber 40 is horizontally divided into a plurality of divisions in the upper part of the growth chamber formed in the chamber 20, and can be introduced into the first to fourth inflow holes 32a to 32d in a separated state. is there. In the case of this embodiment, the separation chamber 40 is constituted by the first to fourth chambers 40a to 40d, and the first to fourth chambers 40a to 40d are formed by the first to fourth partition walls 33a to 33d described above. It is partitioned. As a result, the first chamber 40a has a circular shape, and the second to fourth chambers 40b to 40c have an annular shape arranged concentrically so as to surround the first chamber 40a.

  The susceptor unit 50 is a member serving as a mount unit on which the SiC semiconductor substrate 70 is installed. The upper surface of the susceptor unit 50 is an installation surface of the SiC semiconductor substrate 70. In the present embodiment, the susceptor unit 50 has a disk shape. The susceptor unit 50 is provided with a rod-like support shaft 51 extending downward. Although not shown, the support shaft 51 is drawn to the outside from the bottom surface 24 of the chamber 20 and can be rotated by being connected to a rotation mechanism (not shown).

  The heater 60 is configured by a disk-shaped heater or the like facing the installation surface of the SiC semiconductor substrate 70 in the susceptor unit 50. The heater 60 is externally energized through a wire (not shown). Thus, the heater 60 heats the SiC semiconductor substrate 70 from the back surface side of the susceptor unit 50 to a temperature suitable for the growth of the SiC semiconductor layer 80.

  Although not shown, the inside of the chamber 20 can be controlled to a reduced pressure atmosphere by a pressure reducing device, and at the time of growth of the SiC semiconductor layer 80, only air from the gas cylinders 45 to 48 is removed except for air. The growth chamber can be filled.

  The epitaxial growth apparatus 10 is configured as described above. The SiC semiconductor layer 80 is formed on the surface of the SiC semiconductor substrate 70 as follows, using the epitaxial growth apparatus 10 configured as described above.

  Specifically, while the SiC semiconductor substrate 70 is heated (for example, 1600 ° C.) by the heater 60, a reduced pressure atmosphere (for example, 13.3 kPa = 100 Torr) is set, and the MFCs 41a to 41d, 42a to 42d, 43a to 43d, and 44a to 44d. The various gases are supplied from the gas cylinders 45 to 48 while controlling the flow rate control. Then, various gases flow into the first to fourth chambers 40a to 40d through the gas pipes 41 to 44, and are introduced into the growth chamber of the chamber 20 through the first to fourth inlets 31a to 31d. The gas is thermally decomposed in the vicinity of the heated SiC semiconductor substrate 70, whereby the SiC semiconductor layer 80 is epitaxially grown on the surface of the SiC semiconductor substrate 70. At this time, a p-type epitaxial layer can be grown as the SiC semiconductor layer 80 by introducing TMA containing Al which is an element to be a dopant. Thus, it is possible to obtain an epi-substrate in which a p-type SiC semiconductor having a desired impurity concentration is epitaxially grown on SiC semiconductor substrate 70.

  Here, as described above, the wall surfaces of the first to fourth inlets 31a to 31d among the first to third components 34a to 34c are inclined on the growth chamber side, and the first to fourth inlets are formed. The opening widths 31a to 31d are gradually widened toward the growth chamber side. For this reason, as shown by the arrows in FIG. 3, the introduction range of various gases can be expanded. Therefore, it becomes possible to supply various gases uniformly to the surface of SiC semiconductor substrate 70 with substantially no in-plane distribution.

  The wall surfaces of the first to fourth inlets 31a to 31d among the first to third components 34a to 34c are the tips of the first to third components 34a to 34c closest to the susceptor 50. It is made to be inclined up to and has a structure without a flat surface at the tip. For this reason, it is possible to suppress the occurrence of gas flow stagnation at the tip of the wall surface. Therefore, convection of the dopant gas can be suppressed, and the carrier concentration (in the case of this embodiment, the impurity concentration of the p-type impurity) contained in the SiC semiconductor layer 80 can be adjusted with good controllability. Therefore, it is possible to realize a structure in which the carrier concentration is sharply changed in the depth direction of the SiC semiconductor layer 80 to be epitaxially grown. Specifically, as shown by the solid line in FIG. 4, the change of the carrier concentration in the depth direction of SiC semiconductor layer 80 changes rapidly and does not become a gradual change as shown by the broken line in FIG. Can be.

Second Embodiment
A second embodiment of the present invention will be described. The present embodiment is the same as the first embodiment except that the configuration of the inlet 30 is modified with respect to the first embodiment. Therefore, only the parts different from the first embodiment will be described.

  In the first embodiment, all the various gases are introduced from the gas inlets 31a to 31d in a mixed state, but in the present embodiment, at least a part of the various gases are introduced separately.

  As shown in FIG. 5, pipe members 31aa to 31da are disposed at the gas inlets 31a to 31d. The tips of the pipe members 31aa to 31da are root positions of the inclined portions of the wall surfaces constituting the first to fourth introduction ports 31a to 31d in the first to third constituent portions 34a to 34c (mostly with the growth chamber). It is made to project more than the opposite position).

In such a configuration, Si source gas (for example, TCS), C source gas (for example, C ₃ H ₈ ), dopant gas (for example, TMA), and carrier gas (for example, H ₂ , inert gas) from the inside of the pipe members 31aa to 31da. ). Further, a purge gas (for example, H ₂ ) is introduced from the outside of the pipe members 31aa to 31da among the gas inlets 31a to 31d. Here, the purge gas is the same gas as the carrier gas, but may be a different gas.

  Thus, the purge gas may be introduced around the Si source gas, the C source gas, the dopant gas, and the carrier gas. With such a structure, it is possible to further suppress the adhesion of the deposit to the inlet component 34.

  In the case of such a configuration, various gases are not mixed in the gas pipes 41 to 44, but at least a Si raw material gas, a C raw material gas, a dopant gas, a carrier gas, and a purge gas are separate pipes. Need to be supplied at. Also, in the first to fourth chambers 40a to 40d, the Si source gas, the C source gas, the dopant gas, and the carrier gas are introduced, the chamber connected to the inside of the pipe members 31aa to 31da, and the purge gas are introduced, and the pipe member 31aa. It is necessary to divide into the room connected with the outside of ~ 31 da.

Third Embodiment
A third embodiment of the present invention will be described. The present embodiment is also the one in which the configuration of the inlet 30 is modified with respect to the first embodiment, and the other parts are the same as the first embodiment, so only the parts different from the first embodiment will be described.

In the present embodiment, as shown in FIG. 6, the gas introduction ports 31 a to 31 d on the base side, which are disposed on the base side opposite to the tip side of the introduction port constituting portions 34 a to 34 c, are provided. In addition to that, the fifth to seventh gas inlets 31e to 31g on the tip end side which passes through the tip end closest to the susceptor portion 50 among the inlet ports constituting portions 34a to 34c are formed. Then, Si source gas (for example, TCS), C source gas (for example, C ₃ H ₈ ), dopant gas (for example, TMA), and carrier gas (for example, H ₂ , inert gas) from the fifth to seventh gas introduction ports 31e to 31g. ). The introducing a purge gas (e.g., H ₂₎ from the first to fourth gas inlet 31 a to 31 d.

  As described above, the fifth to seventh gas introduction ports 31e to 31g are formed so as to pass on the line passing through the tip portion closest to the susceptor 50 among the introduction port constituting portions 34a to 34c, and the Si raw material is formed therefrom. The purge gas may be introduced around the gas, the C source gas, the dopant gas, and the carrier gas. With such a structure, the surroundings of the Si source gas, the C source gas, the dopant gas, and the carrier gas do not pass through the inclined wall surfaces in the inlet port constituent portions 34a to 34c. It becomes possible to control the adhesion of the deposit to it.

  Even in such a configuration, various gases are not mixed in the gas pipes 41 to 42, but at least the Si source gas, the C source gas, the dopant gas, the carrier gas, and the purge gas are separated. It needs to be supplied by piping. In addition to the first to fourth chambers 40a to 40d, fifth to seventh chambers 40e to 40f are provided, and Si source gas, C source gas, dopant gas, and carrier gas are provided to the fifth to seventh chambers 40e to 40f. Need to be introduced.

Fourth Embodiment
A fourth embodiment of the present invention will be described. The present embodiment is the same as the second embodiment except that the configuration of the inlet 30 is modified with respect to the second embodiment. Therefore, only the parts different from the second embodiment will be described.

  In the present embodiment, the tip of each of the inlet configuration parts 34 a to 34 c is provided with a heating unit. Specifically, as shown in FIG. 7, a heater 37 by resistance heating is provided as a heating means at the tip of each of the inlet constructions 34a to 34c. Thus, by providing the heater 37, for example, the tips of the introduction port constituent portions 34a to 34c, specifically, are inclined to a temperature equal to or higher than the adhesion temperature (for example, 1200 ° C.) of Al contained in the dopant gas. Heat the wall. In this way, it is possible to further suppress the adhesion of the deposit to the inlet configuration part 34.

  Here, the tips of the introduction port constituting portions 34a to 34c are made of a material different from the root portion (SUS) so that the cooling by the cooling mechanism 35 and the heating by the heater 37 can be thermally separated. . In this case, since it is necessary to prevent sublimation by SiC at a high temperature to form a pollutant for SiC, for example, carbon and high melting point metal carbide (TaC (tantalum carbide), NbC (niobium carbide), etc.) Are used to form the tips of the inlets 34a to 34c.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and appropriate modifications can be made within the scope of the claims.

  For example, with respect to the inclination of the tip of each of the inlet configuration parts 34a to 34c, the cross-sectional shape does not necessarily have to be linear, and the expanded curved shape as shown in FIG. 8 (a) or FIG. 8 (b) It may be in the shape of a concave curve as shown in FIG. In addition, it is sufficient that the flat surface is not formed at the tip of each of the introduction port forming portions 34a to 34c, and for example, it may have a rounded shape as shown in FIG.

  Moreover, what can be combined between each embodiment can also be combined. For example, the heater 37 of the fourth embodiment can be applied to the structure of the first and third embodiments.

  Moreover, in each said embodiment, although it is set as the structure where the inlet-port structure parts 34a-34c were isolate | separated, the gas inlet ports 31a-31d are dotted instead of making it a line form, and each inlet-port structure parts 34a-34c. It can also be set as the structure which connected. However, in that case, a flat surface will be formed between the respective gas inlets 31a to 31d, which may cause deposits or convection of the gas flow, so the gas is preferably used. The inlets 31a to 31d may be line-shaped.

  Further, in each of the above embodiments, the introduction port components 34a to 34c are annular members arranged concentrically. However, this is merely an example, and it may be a concentric frame member. .

DESCRIPTION OF SYMBOLS 10 epitaxial growth apparatus 20 chamber 30 inlet 31a-31g gas inlet 34 inlet structure part 35 cooling mechanism 37 heater 40 separation room 50 susceptor part 70 SiC semiconductor substrate 80 SiC semiconductor layer

Claims (8)

A chamber (20) constituting a growth chamber;
A susceptor portion (50) provided in the growth chamber configured in the chamber and constituting an installation surface on which a silicon carbide semiconductor substrate (70) is installed;
A plurality of separation chambers (40) into which a Si raw material-containing gas, a C raw material-containing gas, and a dopant gas containing an element serving as an impurity of a silicon carbide semiconductor are introduced, and the gases introduced into the separation chamber An inlet (30) having a gas inlet (31a to 31d) to be introduced into the
A heater (60) for heating the silicon carbide semiconductor substrate;
The silicon carbide semiconductor substrate is introduced by introducing the Si source-containing gas, the C source-containing gas, and the dopant gas into the growth chamber through the gas inlet while the silicon carbide semiconductor substrate is heated by the heater. An epitaxial growth apparatus for epitaxially growing a silicon carbide semiconductor layer on the substrate,
The inlet divides the plurality of separation chambers and the growth chamber and constitutes the gas inlet, and has an inlet structure (34) provided with a cooling mechanism (35) therein.
The inlet component is configured to have a plurality of frame-shaped components (34a to 34c) arranged concentrically, and the gas inlet is configured between the plurality of components. And a wall surface of the plurality of components constituting the gas inlet is inclined with respect to a direction from each of the plurality of separation chambers toward the growth chamber. An epitaxial growth apparatus characterized in that the wall surface is inclined to a tip of the plurality of constituent parts closest to the growth chamber. Wherein the plurality of configuration unit, an epitaxial growth apparatus according to claim 1, characterized in that it is an annular concentrically arranged.
  The epitaxial growth apparatus according to claim 1, wherein the introduction port component is cooled to 200 ° C. or less by the cooling mechanism.   Pipe members (31aa to 31da) are arranged at the gas inlet, and the Si raw material containing gas, the C raw material containing gas, the dopant gas and the carrier gas are introduced from the inside of the pipe member of the gas inlet. 4. The epitaxial growth apparatus according to any one of claims 1 to 3, wherein a purge gas is introduced from the outside of the pipe member.   5. The epitaxial growth apparatus according to claim 4, wherein the pipe member protrudes closer to the growth chamber than a position on the opposite side of the growth chamber in a portion where the tip is inclined in the wall surface. 6. . In the introduction port configuration portion, the gas introduction port is added to the base side gas introduction port as a root side gas introduction port arranged on the root side opposite to the tip side of the introduction port configuration portion. The gas inlet (31e to 31g) on the tip end side is formed to pass through the tip on the susceptor part side of the inlet port constituting part,
The purge gas is introduced from the gas inlet on the base side, and the Si raw material containing gas, the C raw material containing gas, the dopant gas and the carrier gas are introduced from the gas inlet on the tip side. An epitaxial growth apparatus according to any one of Items 1 to 3.   The epitaxial growth apparatus according to any one of claims 1 to 6, wherein a heating means (37) for heating the inclined portion of the wall surface is provided at the tip of the introduction port forming portion.   The epitaxial growth apparatus according to claim 7, wherein the inclined portion of the wall surface is heated to 1200 ° C or higher by the heating means.

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